Heterochromia of the eyes in humans. What determines the color of a person's eyes? One eye is blue the other is green in humans

11.05.2020

What do Alexander the Great, Mila Kunis, Jane Seymour and David Bowie have in common? In addition to the fact that they are all personalities, whose names are well known to many people around the world, all four have eyes of different colors. In other words, they have heterochromia, a fairly rare condition that occurs in less than 1% of the world's population. What is heterochromia - a disease or an exceptional feature?

What causes heterochromia?

The color of a person's eyes is determined by the iris, or iris. Depending on the content of melanin pigment in its cells and the nature of its distribution, the iris can have a color from light blue to almost black. The color of the iris develops during the first months after birth, the final eye color is established in the first or second year of life, and the amount of melanin determines how dark the eye color will be. The less melanin, the lighter the eyes will be, and vice versa. In some cases, when the concentration of melanin and its distribution are not uniform, a condition known as iris heterochromia can occur.
Heterochromia (from the Greek ἕτερος - "different", "different"; χρῶμα - "color") is a different color of the iris of the right and left eyes or unequal color of different parts of the iris of one eye. It is the result of some excess or lack of melanin in different eyes, where one eye may be less pigmented and the other more. Heterochromia is quite rare and occurs in less than 1% of the world's population. It can be hereditary or acquired due to eye injury or the development of certain diseases. Many people believe that multi-colored eyes give the face a unique character. If one eye is blue and the other brown, then the difference is noticeable immediately. To see that one eye is gray and the other blue is more difficult, and only by looking closely can you tell the difference.

Types of heterochromia

Depending on the type of staining of the iris, several types of heterochromia are distinguished: complete, in which both eyes have a different color (Fig. 1); partial, or sectoral, when several different color shades are presented at once in the iris of one eye (Fig. 2); central, when the iris has several full color rings (Fig. 3). The most common type is complete heterochromia, where, for example, one eye is brown and the other blue. The second type, partial heterochromia, is in some cases the result of inherited diseases such as Hirschsprung's disease and Waardenburg's syndrome. In women, heterochromia occurs more often than in representatives of the strong half of humanity. In medical practice, there are known forms of heterochromia resulting from damage to the iris: simple - abnormal coloration of the eye membrane with congenital weakness of the cervical sympathetic nerve; complicated - uveitis with Fuchs syndrome (a chronic disease in which one of the eyes is affected, expressed by a change in the color of the iris).
Some people have developed heterochromia after trauma to the eye with an iron or copper foreign body, when it was not removed in a timely manner. This process is called metalosis of the eye, and when it occurs, a number of symptoms appear, characteristic of inflammation of the eyeball, and in addition, the color of the iris changes. Often, with metalosis of the eye, the iris becomes brown-rusty, but it can also be green-blue.
Can the color of the iris be restored? With congenital heterochromia, medical treatment will not help, but colored or tinted contact lenses can even out the visible color of the eyes. In case of metallosis, the color of the eyes can be restored after the successful removal of a foreign body, and in case of inflammation of the eye, with complete cure.

Heterochromia in animals

In animals, the phenomenon of heterochromia is more common than in humans (Fig. 4). You can see this anomaly in cats, dogs, horses, cows and even buffaloes.

Figure: 4. Animals with complete heterochromia

Most often, complete heterochromia appears in cats with partial or full white color, for example, in the Turkish Angora and Turkish Van breeds. According to legend, the favorite cat of the Prophet Muhammad - Muizza - had eyes of different colors. Among dogs, heterochromia is often seen in breeds such as the Siberian Husky. Horses with complete heterochromia usually have one brown eye and the other white, gray, or blue eye, with eye heterochromia occurring in piebald animals.
As a rule, complete heterochromia is found in animals: one eye is blue or gray-blue, and the other is colored yellow, copper or brown. Partial heterochromia among animals is a rarer phenomenon, it is characterized by partial blotches of a color different from the main color of the iris. More often than in other animals, partial heterochromia occurs in Australian Shepherd and Border Collie dogs.
Heterochromia is a condition whose gene is inherited; it does not carry any complications or inconveniences to the animal. Its presence does not affect visual acuity and photosensitivity, and the pupil reacts to light with a sharp narrowing, like in ordinary animals. However, breeding animals with heterochromia is not recommended, it is considered a marriage of the breed, although some animal lovers specifically select for themselves odd-eyed pets.

Should you worry if you have heterochromia?

Of course, heterochromia is an abnormality, but its presence does not necessarily mean the presence of hidden health problems. Nevertheless, there is evidence that heterochromia may accompany some hereditary diseases. One example of such diseases is Waardenburg's syndrome, in which children develop the following clinical signs: congenital hearing loss of varying degrees, a gray strand above the forehead, and heterochromia. Another example is a disease like neurofibromatosis, which affects many organs and even entire systems. Outwardly, it is accompanied by the presence on the skin of many spots of a coffee-milk color, neurofibromas and pigmented hamartomas of the iris (Bream nodules). Experts recommend not only children, but also adults with congenital or acquired heterochromia to undergo an annual medical examination.
If you notice a sudden change in the color of the iris, the appearance of heterochromia, this may be due to a health condition. In this case, it is necessary to consult an ophthalmologist who will conduct a thorough examination and identify any problems.

Diagnostics and treatment of heterochromia

Let's say right away that heterochromia itself is not a disease. However, it can be a consequence of some serious diseases and therefore requires a medical examination by an ophthalmologist. If pathologies are found during the examination, the doctor will give a referral for tests and other laboratory tests. Depending on the type of pathology detected, medical or surgical treatment will be carried out. When the disease is completely cured, the color of the eyes can be restored. With congenital pathology, it will be possible to change the shade only with help.

Notable individuals with heterochromia

The mass media pay special attention to the description of the appearance of famous people - actors, singers, athletes, politicians, looking for the slightest deviations from the norm. The British version of Wikipedia, when asked, will give you a list of celebrities with one type of heterochromia or another.
So, partial or complete heterochromia was noted in Hollywood actress Mila Kunis: her left eye is brown, her right eye is blue; British actress Jane Seymour: the right eye is a combination of green and brown, the left eye is green; American actress Kate Bosworth: left eye - blue, right - blue and brown; sectoral heterochromia in both eyes is found in Canadian actor Kiefer Sutherland - a combination of green and blue, in British actor Benedict Cumberbatch; acquired heterochromia after trauma in a fight was noted in British rock musician, singer and producer David Bowie (Fig. 5). Many other celebrities also have heterochromia.

Figure: 5. Compiled a whole list of celebrities with one or another type of heterochromia.
On the picture (top down): Kate Bosworth, David Bowie, Jane Seymour, Mila Kunis

The fact that Alexander the Great had complete heterochromia is mentioned by the Greek historian Arrian, who described Alexander as a strong, attractive commander, one of whose eyes was black as night and the other as blue as the sky.
There are many examples of heterochromia among famous literary characters: Woland ("the right eye is black, the left eye is for some reason green") from "The Master and Margarita" and Lieutenant Viktor Myshlaevsky from the "White Guard" Mikhail Bulgakov, tank commander Vasily Semenov in the book by Yanush Pshimanovsky "Four a tankman and a dog.
Different eye colors always attract attention, but after reading this article, you will understand that this is most often just an abnormal deviation from the norm, hereditary or acquired.

1 See: Heterochromia iridum // Wikipedia, the free encyclopedia. URL: http://en.wikipedia.org/wiki/Heterochromia_iridum (date accessed: 22.09.2014).
2 See: Heterochromia // Wikipedia - the free encyclopedia [Site]. URL: http://ru.wikipedia.org/wiki/% C3% E5% F2% E5% F0% EE% F5% F0% EE% EC% E8% FF (date accessed: 22.09.2014).
3 See: Neurofibromatosis // Neboleem.net. Medical portal [Site]. URL: http://www.neboleem.net/neirofibromatoz.php (date accessed: 22.09.2014).
4 See: Heterochromia, or People with Colored Eyes // facte.ru. Cognitive magazine [Site]. URL: http://facte.ru/man/6474.html#ixzz336UHypus (date of access: 22.09.2014).
5 See: What causes different colored eyes? // essilor. URL: http://news.essilorusa.com/stories/detail/what-causes-different-colored-eyes (date accessed: 22.09.2014).
6 See: List of people with heterochromia // Wikipedia, the free encyclopedia. URL: http://en.wikipedia.org/wiki/List_of_people_with_heterochromia (date accessed: 22.09.2014).
7 See: Alexander the Great // Wikipedia, the free encyclopedia. URL: http://en.wikipedia.org/wiki/Alexander_the_Great (date accessed: 22.09.2014).

Olga Shcherbakova, Veko magazine, 8/2014

Heterochromia (from the Greek. ἕτερος and χρῶμα , which means "different color") is a rather rare occurrence when a person has a different eye color. Characteristically, eye heterochromia in humans can manifest itself not only in a different color of the right and left visual organs, but also in the color of the iris, which can occur due to the uneven distribution of melanin (coloring pigment) in the shell.

Eyes of different colors. What should you know about?

On a note! If melanin is unevenly distributed in one or two eyes, or there is too little or too much of it, this leads to such a phenomenon as heterochromia.

The specific color depends on what color the pigment is in excess / deficiency (it can be blue, yellow and brown). As noted earlier, the phenomenon is rare (about 1% of the world's inhabitants) and, which is typical, more often in women than in men. However, no physiological / anatomical prerequisites for such gender “inequality” were identified.

Heterochromia is not considered a pathology, since, in addition to the external effect (eyes of different colors do not always look attractive), it is not accompanied by any visual disturbances. But this applies only to those cases when the condition is congenital, that is, not associated with concomitant eye diseases.

The main types of heterochromia

Depending on the factors that cause heterochromia, it can be hereditary or acquired. According to another classification, it is divided into three types, let's get acquainted with them.

Table. Varieties of heterochromia.

Name, photo	Short description
	Rings on the iris are clearly visible, differing from the main color of the shell.
	On one eye, areas are visible that are colored by pigments of different shades / colors.
	The iris of one eye is completely colored. As a rule, in such cases, one eye is brown and the other blue.

People with different colored eyes. Photo

In the photo below you can see the different types of the phenomenon described in the article.

Why does heterochromia appear

So, why can a person's eyes have different colors? The main reasons, as well as the prerequisites for the development of this phenomenon, include:

heredity;
all kinds of injuries, for example - the ingress of foreign objects into the organs of vision. These injuries can cause darkening of the eyes. And if, say, the gray / blue iris is damaged, then it may eventually turn brown either;

fuchs syndrome. It is characterized by developing inflammatory processes in the tissues of the organs of vision. Other signs include blurred vision, as well as complete / partial loss of vision;
side effects of some of the drugs used to treat it;
neurofibromatosis.

Note! In most cases, it is hereditary heterochromia that is observed. Therefore, if the phenomenon was detected in one of the parents, then it is more than 50% likely to be in the child (to a lesser or greater extent).

Depending on the cause of the occurrence of heterochromia, it can be simple, complicated and acquired. Acquired form - This is when the color of the eye changes after the use of glaucoma medications or due to injury. In addition, it can appear after copper or iron gets into the eyes - in the first case, the phenomenon is called chalcosis, and in the second, siderosis.

Complicated heterochromia develops due to Fuchs syndrome, although it is difficult to diagnose it in some cases, because the eye does not always undergo significant changes. Although there are additional signs that determine the complicated form of the phenomenon:

deterioration of vision;
the appearance of precipitates (these are floating white formations in the eye);
dystrophic changes in the iris;
cataract.

As for simple heterochromia, then it develops without any disease; often reveal a simple congenital form, which is most pronounced in children under the age of 2 years.

Although the reasons may be different, not entirely normal - for example, Horner's or Waardenburg's syndrome.

Video: Why do people have different colors of eyes?

About diagnosis and treatment

Important information! Treatment of heterochromia is not always mandatory, although after a number of diagnostic measures, a specific therapy regimen may be prescribed (here it all depends on the specific cause of development).

As a rule, experts determine all this visually. Then, if required, a special examination is prescribed, thanks to which it is possible to identify pathological changes in the tissues, which led to heterochromia. If, in addition to changing the color of the iris, other symptoms are not observed, and vision does not deteriorate, then no treatment is required. By the way, in such cases, even with the help of medications or surgery, the natural color of the iris cannot be changed.

If the anomaly is provoked by a violation of the integrity of the iris or some kind of eye disease, then steroid drugs will be used for treatment. With clouding of the lens, if steroids have not had any effect, vitrectomy is prescribed (surgical removal of the vitreous body - partial or complete).

Note! If the color of the iris has changed due to the fact that metal shavings have got into the eyes, then the problem is solved by eliminating the foreign body and then conducting drug therapy. After that, the color of the eye should be normalized.

Video: Change eye color without lenses

As you can see, in the case of an acquired form of heterochromia, it is imperative to visit an ophthalmologist. A qualified specialist will assess how dangerous the anomaly is and, if necessary, prescribe appropriate therapy. And with a congenital form, such an intervention is not required, because heterochromia does not affect vision either positively or negatively.

Celebrities with heterochromia

The media pay special attention to the appearance of celebrities - athletes, singers, actors - and look for the slightest hint of deviation. On Wikipedia, for example, you can find a large list of famous personalities with different eye colors (more or less pronounced). This is, for example, Mila Kunis - an actress of Ukrainian origin has one blue eye and the other brown. Jane Seymour, a popular British actress, also has eye heterochromia, as does Kate Bosworth, Kiefer Sutherland, Benedict Cumberbatch and many others. And David Bowie, by the way, acquired this anomaly - it appeared after an injury received in a fight.

On a note! If you believe the ancient Greek historian Arrian, then Alexander the Great also had a different eye color.

As a conclusion. Heterochromia among animals

But in animals, such an anomaly occurs much more often than in humans. Heterochromia can be seen not only in dogs or cats, but also in cows, horses, and buffaloes.

As a rule, the anomaly manifests itself in whites (partially or completely cats). As for dogs, they may have an anomaly in representatives of breeds such as the Siberian Husky. In horses with heterochromia, one eye is usually white / blue and the other is brown. And one more curious fact: eyes of different colors are observed mainly in animals with piebald color.

Video: Multi-colored eyes in humans (heterochromia)

I wonder how a person feels with a similar difference from the rest? Surely, "disagreeable" people feel a little constrained, realizing that they differ from the rest, even if only slightly. And we, ordinary people, look at them and somewhere in the depths of our souls, or maybe we quite clearly admire it. A person's desire to stand out is quite normal, therefore, the desire to be in the place of those “different” from him is justified. We conclude that you should not be ashamed of your distinctive features, especially since many, as mentioned, are trying to recreate something like that, resorting to certain means.

Although, is this so, do people with different eyes really do not like being such? There is a lot of material that reveals the human side from different sides - meleosophy, which studies moles on the human body, philosophy, psychology, physiology, biology, palmistry and many other directions that are so different from each other. An attempt to characterize a person by eye color was no exception. Tons of articles that describe people with brown, green, blue eyes. But what about a person whose eye color is not the same? Let's figure out what different eye color means for people!

Congenital and acquired "discord"

In science, the phenomenon of people with multi-colored eyes was considered from a genetic point of view and is called heterochromia - a different color of the iris of one eye from another. It is the result of a relative excess or lack of melanin. But there is also acquired "discordance", for example, as a result of trauma, in people with glaucoma or tumors.

Psychological portrait of people with different eye colors

Egocentrism

Such people are characterized as fearless, unpredictable and extraordinary personalities. They are incredibly generous. Against the background of these weighty positive qualities, there is a clear negative - egocentrism in a pronounced form. "How is it that they didn't pay attention to me ?!" It is very difficult to get along with egoists; they require an excessive amount of attention. But here's the paradox, people with different iris colors love loneliness. Strange, isn't it? Although, why be surprised? Against this background, they have a narrow circle of friends whom they value and love. Well, how not to appreciate those who endure and accept your egoism?

Striving for the ideal

Women - "disagreeable" strive for the ideal. Physique can be overweight, so they often resort to diets. However, this does not prevent them from enjoying their appearance, there is simply "no limit to perfection." Ladies are delicate by nature, they love poetry, music, dances, they are very cheerful.

Measured lifestyle

The life schedule is not tight, if some bright events happen, it is quite rare. True, this does not particularly upset them, on the contrary, it makes them appreciate what they have, and will be imprinted for a long time in their memory. They themselves can arrange a holiday for themselves and do it, thanks to their good organizational skills and imagination.

Patience and endurance

Positive qualities include good patience and endurance. You may not even know about their problems - they spread about their worries or grievances only when the boiling point is reached. And then, only the closest ones will know. They do not seek to jump over their heads, they are content with their current situation.

Ideal wives

In relationships, at first glance, they are windy, but if the "disagreement" and left you, it is only because for her you are not the one and only, and there can be a lot of them. When she finds that one, it will be "love to the grave," with dramatic changes in behavior. It will be possible to see, it would seem, in a riotous girl an excellent hostess who will always maintain comfort in the house, and if you wish, will share useful wisdom. Don't miss the tips on deaf ears. It will be possible to envy the husbands of such ladies, because all egoism will turn in a completely different direction - she will "live by her man."

So, in addition to the fact that such a girl will be an excellent housewife, a caring wife, she, of course, will not forget to follow her appearance. For any man, it seems to me, this is the ideal wife. True, there are qualities that a husband can accept, or maybe not categorically. Women with "disagreement" are addicted to alcohol, but, by virtue of their intelligence, they avoid it. But smoking, having tried it once, it is possible that they will never be able to quit.

Stubbornness and straightforwardness

People with multi-colored eyes are characterized by stubbornness and capriciousness, do not forget about this. In a dispute or quarrel, they will stand their ground to the end. They are rude, but only in extreme cases when the opponent cannot understand otherwise. They try not to show these qualities to others.

Try to choose words when communicating with them. They easily forgive, but they will remember the offense for a long time. They do not know how to hint and themselves are not able to understand hints, which testifies to their straightforwardness. "Better a bitter truth than a sweet lie" is the motto with which they go through life.

We hope that now it will be easier for you to understand such unusual and contradictory people.

My friend has a kitten, fluffy and very funny. But his eyes are different colors - one blue, the other green. Please tell me it doesn't affect his health, does he see well? And is this normal? Darya

Hello Daria! And, you know, your friend is lucky! It is believed that having such a miracle as a cat with different eye colors is a good luck.

Let's consider this interesting phenomenon in more detail. The difference in the color of the iris is called disagreement or heterochromia (from the Greek words "heteros" - different, different and "chromium" - color) - different colors of the iris of the right and left eyes or unequal color of different parts of the iris of one eye. In other words, the term heterochromia both the presence of a section (segment) of a different color in one eye, and the case when both eyes have a completely different color are called.

Heterochromia occurs in some species of animals, and even in humans, but is most common in cats. The most common occurrence is complete heterochromia, when a cat has one eye that is entirely orange, golden, yellow or green and the other blue. Cases of partial heterochromia, when only part of the eye is painted in a different color, are much less common.

Cause of heterochromia lies in the different concentration and uneven distribution of melanin - a natural coloring pigment - in the iris. The eye affected by heterochromia may be hyperpigmented (excess melanin) or hypopigmented (lack of melanin).

Now attention! In albinos, melanins may have a reduced concentration and even be completely absent (!). This explains the fact that blue eye color is more often observed in white cats or in cats with a high percentage of white in color ... Therefore, disagreement is especially common among Angora or Turkish Van cats (originally white cats).

And to make it completely clear (or completely incomprehensible :-)) littlegenetandki:

The peculiarity of the white color is that its gene is one of the strongest in domestic cats in terms of its effect not only on blocking coat pigmentation, but also on the development of the rudiments of the nervous system. Under its influence, changes in the organs of sight and hearing can occur.

Due to the gene for white color, there may be no pigment in the iris of the eye, which visually looks like blue. It can be bilateral (both eyes) or unilateral (only one eye) blue eyes. It has been found that in completely white cats with different colored eyes, deafness usually occurs in the ear located on the side of the blue eye.

The discord of completely white cats is formed under the influence of the dominant and dangerous gene W - White, which in homozygous form (when only this gene is present) is considered lethal, that is, leading to the death of kittens even inside the womb. Therefore, all pure white cats can only be heterozygous, that is, a pair of “non-white” is necessarily attached to the gene for white color, due to which colored kittens are born in litters from white parents.

Disagreement does not affect vision (!) therefore heterochromia is not considered a disease.

Agree that cats with different eye colors look very mysterious, and certainly, in modern terms, cool!

Incredible facts

Brown-eyed people are more credible than blue-eyed people, scientists have found out.

However, as researchers from Charles University in Prague, eye color itself is not credible. When a group of volunteers were shown photographs of the same men, whose eye color had been artificially changed in different photographs, they were considered more reliable.

This suggests that trust is not caused by the color of the eyes itself, but by the facial features inherent in brown-eyed people.

For example, brown-eyed men tend to have a rounder face with a wide chin, a wider mouth with raised corners, large eyes, and closer set eyebrows. All these qualities indicate masculinity and therefore inspire confidence.

In contrast, blue-eyed members of the stronger sex are more likely to have facial features that are perceived as a sign of cunning and variability. These are usually small eyes and a narrow mouth with drooping corners.

Women with brown eyes are also considered more reliable than blue-eyed women, but the difference is not as pronounced as men.

One of the first features that attract us to a person is his eyes, and especially his eye color. Did you know which eye color is considered the rarest, or why eyes can be red? Here are some interesting facts about human eye color.

Brown eye color is the most common eye color

Brown eye color is the most common eye color in the world, excluding the Baltic countries. It is the result of the presence of a large amount of melanin in the iris, which absorbs a lot of light. People with very high concentrations of melanin may look like they have black eyes.

Blue eye color is a genetic mutation

All people with blue eyes have one common ancestor. Scientists have traced a genetic mutation that led to the appearance of blue eyes and found that she appeared 6,000 - 10,000 years ago... Until that time, there were no blue-eyed people.

Most of the people with blue eyes are in the Baltic and Nordic countries. In Estonia, 99 percent of people have blue eyes.

Yellow eyes - wolf eyes

Yellow or amber eyes have a golden, tan or copper hue and are the result of the presence of lipochrome pigment, which is also found in green eyes. Yellow eye color is also called "wolf eyes", as this rare eye color common among animalssuch as wolves, domestic cats, owls, eagles, pigeons and fish.

Green is the rarest eye color

Only 1-2 percent of people in the world have green eyes... Pure green eye color (which should not be confused with marsh color) is a very rare eye color, as it is often eradicated in the family by the dominant brown eye gene. In Iceland and Holland, green eyes are most commonly found in women.

One person may have different colored eyes

Heterochromia is a phenomenon in which one person may have different eye colors... It is caused by an excess or lack of melanin and is the result of a genetic mutation, disease, or injury.

With complete heterochromia, a person has two different colors of the iris, for example, one eye is brown, the other blue. In partial heterochromia, the color of the iris is divided into two differently colored parts.

Red eyes often occurs in albinos... Since they have almost no melanin, their iris is transparent, but looks red due to the blood vessels.

Eye color can change over the course of a person's life. African Americans, Hispanics, and Asians are generally born with dark eyes that rarely change. Most Caucasian children are born with light blue or blue eyes. But over time, as the baby develops, the cells in the iris of the eye begin to produce more of the pigment melanin. Usually, baby's eye color changes by one year, but can be established later by the 3rd, and less often by 10-12 years.

In rare cases, a change in eye color over the course of life can also indicate some diseases, such as Horner's syndrome, some forms of glaucoma, and others.

Eye color formation is a complex process that is genetically determined. There are many combinations of genes that we get from both parents, which will determine the color of your eyes. Here is the most simplified diagram that will help you find out the eye color of an unborn child.